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IRSCredits & Incentives (8800/8900 Series)

Official form guide

Form 8990: 8990

Form 8990 is the Corporate Net Investment Income Tax (NIIT) Return. Corporations, estates, and trusts file it to calculate the 3.8% NIIT on net investment income when modified taxable income exceeds $250,000.

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Form Overview

IRS Form 8990 - 8990

Form 8990 is the Corporate Net Investment Income Tax (NIIT) Return. Corporations, estates, and trusts file it to calculate the 3.8% NIIT on net investment income when modified taxable income exceeds $250,000.

The form captures modified taxable income, net investment income, and the calculated NIIT amount.

Risk Radar

Scan points
  • 1A single mis‑calculated NIIT dollar can trigger penalties and interest.
  • 2Using the regular taxable income instead of modified taxable income
  • 3Omitting certain investment income items (e.g., foreign dividends)
  • 4Applying the 3.8% rate to the wrong base amount
  • 5Failing to attach the form to the primary return

Plain English

If your corporation or trust makes money from investments—like interest, dividends, or capital gains—and its income is high enough, you owe an extra 3.8% tax. Form 8990 tells the IRS how much you owe.

Submission Date

  • Filing date: 2026-01-21 17:10:36
  • Preparation window: collect IDs, supporting records, and signatures in advance.
  • Final review: verify names, dates, and required fields before submission.

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Glossary Terms

income taxinterestincomemoney

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What this form is for

  • Use when modified taxable income > $250,000 and there is net investment income.
  • Do not use for individuals; they file Form 8960.
  • If the entity is a partnership, the partnership files Form 8804/8805 instead.

Form selector

Use this form or another form?

Individual with high investment income

Calculates NIIT for individuals

✓ Verify filing status first

Form 8960

Partnership with NIIT liability

Not clearly stated in the provided official source

✓ Not clearly stated in the provided official source

Form 8804

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Not clearly stated in the provided official source

✓ Not clearly stated in the provided official source

Not clearly stated in the provided official source

Field map

Compact field-by-field guide

6 fields

Entity Info

1 items

Taxpayer Name and TIN

Name and taxpayer ID of the entity claiming the credit.

Requiredtext

Credit Info

1 items

Credit Type

Type of credit or incentive being claimed.

Requiredselect

Calculation

2 items

Qualifying Amount

The base amount used to calculate the credit.

Requiredamount
Credit Amount

Calculated credit amount after applying formulas and limitations.

Requiredamount

Certification

1 items

Supporting Information

Detailed breakdown supporting the credit calculation.

text

Signatures

1 items

Signature

Sign and date the form.

Requiredsignature
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Current form status
IRS

The 2024 edition of Form 8990 is available on IRS.gov. Verify the edition date on the PDF before using it.

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Quick Facts

Corporations, estates, and trusts with modified taxable income over $250,000 must file.
The form captures modified taxable income, net investment income, and the calculated NIIT amount.
File with the entity’s original income tax return (Form 1120, 1120‑F, 1041, etc.) for the same tax year, generally by the return’s due date, including extensions.
Attach Form 8990 to the original return and mail to the address listed in the return’s instructions, or file electronically if the return is e‑filed.
Errors can lead to underpayment penalties, interest, or an audit of the NIIT calculation.
1. Gather the entity’s taxable income, adjustments, and investment income statements. 2. Compute modified taxable income on Schedule A of Form 8990. 3. Compute net investment income on Schedule B. 4. Apply the 3.8% rate on the lesser of the two amounts. 5. Enter the result on the main form and attach to the tax return.

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Source transparency

Copyright & Licensing - US Government Forms

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Public DomainCreated by the U.S. federal government. Not subject to copyright (17 USC § 105). Freely copyable without restriction.
Public DomainCreated by the U.S. federal government. Not subject to copyright (17 USC § 105). Freely copyable without restriction.
Public DomainCreated by the U.S. federal government. Not subject to copyright (17 USC § 105). Freely copyable without restriction.
Public DomainCreated by the U.S. federal government. Not subject to copyright (17 USC § 105). Freely copyable without restriction.
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